To a clean jar add the active sourdough starter.

Next, add the water and stir until the water becomes “milky.”

Then add the sugar and stir until most of it has dissolved.

Lastly, add the flour and mix until no traces of flour are left. The stiff starter is dough-like and best mixed with a fork, your hand, or a silicone spatula.

Cover the jar loosely with the cap and the starter should double in size within 8-12 hours.

Ensure your sweet starter has doubled in size before mixing the dough. It will need 8-12 hours to rise. Refer to "notes" section to choose when to mix it.

In a small saucepan, heat the milk and butter over low to medium heat until the butter melts. Allow the mixture to cool for 5-10 minutes.

Once cooled add the mixture to a mixing bowl and dissolve your sweet starter & the sugar in the mixture by mixing it with a fork. It's okay if the starter does not dissolve completely.

Next, add your egg, flour, and salt. Mix with a silicone spatula for best results. It will be wet and sticky.

Cover with plastic wrap and let it rest for 30 minutes.

After 30 minutes, knead the dough into a smooth ball (5-8 minutes). Add additional flour during this process to assist with stickiness. It will come together nicely with a little elbow grease and patience!

Place the dough in a generously coated buttered bowl and cover it with plastic wrap and let it sit overnight or until doubled in size (8-12 hours).

Optional: perform 1 stretch and fold an hour into the bulk rise (this helps with a better overall rise especially if kneading by hand).

When the dough has doubled in size and is ready to be shaped, lightly flour your work surface to prevent sticking.

Remove the dough from the bowl and shape it into a rough rectangle shape and let it rest for 10 minutes (this is to relax the gluten and make rolling easier).

Lightly flour your rolling pin and your dough and begin to roll the dough out into approximately a 16×12 rectangle.

In a medium-sized mixing bowl, use your silicone spatula to mix 3 tablespoons (save 1 tablespoon for brushing the dough) of the softened butter by itself. Once a creamy texture, add the cinnamon, sugar, brown sugar, flour, and mix well.

Take the 1 tablespoon of softened butter and melt it. Using a pastry brush, brush the dough with the cooled melted butter. I find this helps the mixture spread better. You can also add a teaspoon of melted butter to the mixture to help soften it a bit.

Using your silicone spatula or spoon, begin to spread the mixture on the dough. Lightly press the mixture into the dough with your hands. Leave about a ½-1 inch border to the edge

Starting from the long side (16 inches) begin to roll the dough tightly, pressing down lightly at each roll. TIP: If you find the dough is too sticky lightly flour your hands to help.

Once fully rolled, make sure the roll is seam side down and begin to lightly mark with your bench scraper 2-inch cuts (totaling 8 rolls).

After the marks are made, begin to cut each roll and place them in your baking pan lined with parchment paper.

Cover with oiled plastic wrap and allow the rolls to sit for 2-3 more hours in the pan or until they have puffed up. Tip: turn your oven on and then off to create a warm environment for the rolls to rise. Sourdough cinnamon rolls can be shaped and refrigerated overnight and baked the following morning.

Preheat your oven to 350 degrees F and bake your cinnamon rolls on the middle rack for 35-40 minutes. Check your rolls at 35 minutes. They should be lightly golden brown and fully cooked through the center.*The internal temperature of sourdough cinnamon rolls should be around 190-200°F (88-93°C) when they are fully cooked. You can use an instant-read thermometer to check the temperature in the center of one of the rolls.

During this time, make the frosting. Using your electric hand mixer, beat the cream cheese and butter together on medium speed in a medium mixing bowl . Mix until they are well combined and have a smooth, creamy texture. This should take about 2-3 minutes.

Pour the vanilla extract in and mix until combined.

Reduce the speed of your hand mixer to low. Slowly add the powdered sugar, about one cup at a time. This prevents a sugary mess and ensures that the powdered sugar is incorporated evenly into the mixture.

After each addition of powdered sugar, increase the mixer speed to medium and continue to blend until the frosting becomes smooth and well combined. Be sure to scrape down the sides of the bowl with a spatula to ensure even mixing (optional: adjust the consistency by adding a teaspoon of milk at a time).

Once the rolls are done baking, allow them to cool for 15 minutes in the pan before transferring them to a wire rack to add the icing. Important: allowing the cinnamon rolls to rest will ensure all the dough has absorbed the butter .

These are best enjoyed the day of, but you can store them on your countertop in an airtight container for 2 days or up to a week in your refrigerator.